<!DOCTYPE html>
<html lang="zh">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="jQuery.min.js"></script>
    <style>
        #weibo {
            padding: 20px 20px;
            width: 400px;
            border: 1px solid #bbb;
        }
        li{
            display: none;
            border-bottom: 1px dashed #ddd;
            width: 200px;
        }
    </style>
</head>

<body>
    <div class="box" id="weibo">
        <span>微博发布</span>
        <textarea name="" cols="30" rows="10" class="txt"></textarea>
        <button class="btn">发布</button>
        <ul>

        </ul>
    </div>

    <script>
        $(function(){
            $('.btn').on('click', function(){
                var $li = $('<li></li>');
                $li.html($('.txt').val() + '<a href="javascript:;">删除</a>');
                $('ul').prepend($li);
                $li.slideDown();
                $('.txt').val('');
            });

            $('ul').on('click', 'a', function(){
                $(this).parent().slideUp(function(){
                    $(this).remove();
                });
            })
        });
    </script>
</body>

</html>